Motorcycle



G. E. RIGBY, MOTORCYCLE. APPLICATION HLED JAN. 14, 1919- 1 34 3 4 Patented Jan. 4, 1921.

2 SHETSSHEET I.

M15 Paws. mm. mm. msazacm. n. c.

6. E. RIGBY. MOTORCYCLE. APPLICATION FlLED MNf M, m9.

Patented Jan. 4, 1921.

2 SHEETSQSHEET 2.

GEORGE E. RIGIBY, OF MANCHESTER, ENG-LAND.

MOTORCYCLE.

Specification of Letters Patent.

Patented Jan. l, M921.

Application filed January 14, 1919. Serial No. 271,130.

To all whom it may concern.

Be it known that I, Gnonon EDWIN Riser, a subject of the King of England, residing at Wanchester, in the Kingdom of England, have invented new and useful Improvements in Motorcycles, of which the following is a specification.

This invention relates to an improved spring frame for motorcycles of the kind in which the rear roadwheel with its own frame is capable of vertically yielding bodily relatively to and without affecting the steadiness of the main frame, and consists in an improved connecting contrivance between the rear-sprung frame and main frame by the adaptation of a single radius arm disposed in the plane of the main frame locking device for said arm, and a controlling spring beneath and practically parallel with said arm and beneath the seat pillar.

In order that my invention may be clearly distinguished from typical arrangements of this kind, I will describe the same fully with reference to the drawings, in which:

Figure 1 is a side elevation showing the invention connected with a portion of the main frame of a motorcycle; Fig. 2 is a plan showing similar parts; Fig. 3 is a sectional elevation of the rear bearing of the radius arm and a portion of the stays attached thereto; Fig. 4c is a side elevation corresponding to Fig. 3; Fig. 5 is a vertical. section to a larger scale of the bearing joint of the radius arm; Fig. 6 is a fractional detail of the spindle connecting the radius arm with the stays; Figs. 78 are similar views to Figs. 12 showing respectively the use of a compensating roller bearing in lieu of the shackle arrangement for the end of the spring; Fig. 9 shows a fraction of a motorcycle with the improvements connected thereto.

The rear fork members which are known as the belt or chain stays carrying the road wheel axle, are pivoted at their forward end to the lower part of the main frame or, for instance, to the gear bracket, or any part connected therewith, the joints being in the nature of a substantial roller or ball bearing which is located as close as possible to the center of the drive or pulley shaft of the gear box in order that the transmission for the drive may be practically unaffected by the rising and falling of the rear wheel center. To the rear extremities of said rear fork, a pair of members or down stays D are pivoted and are extended to a point above the top of the wheel, one on either side of the latter. By this invention the top ends of said members or stays D are pivotally connected to one end of a single radius arm E.

This pivotal connection takes the form of a long bearing E which is transverse to the longitudinal axis of the machine. The said radius arm E is longitudinally disposed at the rear of the seat pillar and in the plane of the main frame, and is pivoted at its forward end to another transverse bearing E connected to the main frame X or may be pivoted to plates F attached thereto, thus insuring improved lateral stability and synchronizing movements of the spring.

in a modification of the invention, said radius arm may be of a bifurcated construc tion, but the previously described arrange ment is deemed preferable. S is the seat support.

The locking device is effected as follows:

The rearward lug which forms the trans verse bearing E for the radius arm E so designed as to carry a notched drawbolt or cross-pin E capable of being turned around for half a turn. The pin E is interlocked with the shaft or notched spindle D where on the rear stays D are secured and on which the rearward end of the radius arm oscillates. This locking principle is adaptable to all the pivotal joints of the machine; the object is to transform the pivotal spring frame into a rigid frame so that if the spring should break or a coupling give way, the rider can complete his journey by locking the pivotal joints.

The springing effect may be accomplished by the use of a longitudinally disposed spring of a laminated type, such as H, anchored at H, in a housing on the main frame or seat bracket, or near the forward end of the radius arm or fork. The eye end of the spritng may be attached by means of a shacklefi suspended from the rearward portion of the radius arm E which is in turn supported by means of the rear stays D It is therefore obvious that the movement of the radius arm E is capable of actuating other kinds of springing method by simply connecting various shapes or forms of hellcrank levers to said radius arm. An eccentric or screw arrangement may be provided for the spring adjustment, which is capable of Epnsioning the spring to carry the various loa s.

Another method of attaching the eye-end of a laminated spring is shown at Figs. 78 consisting of a spring compensating roller bearing M of known construction and for which purpose the radius arm is bifurcated to receive the spring between its arms, as will be readily understood.

I claim:

1. In a motorcycle, a main frame, a prolongating radius arm in the plane of said frame, a locking joint at the rear end of and a spring longitudinally beneath said arm, and a rear Wheel frame pivotally connected With the arm and With the main frame.

2. In a motorcycle, a main frame, a rear wheel frame, a single radius arm connecting the upper frame parts, and crosswise ar' ranged notched pins forming locking joints for the said arm to the attached frame parts.

GEO. E. RIGBY. 

